I think this change can possibly make sense when we have replaced Zope
2 authentication with Zope 3s, and when we have replaces Zope 2
publisher with Zope 3s and when we have replaced the Zope 2 traversal
with Zope3s, and maybe a couple of other things.

Advertising

At that point, Zope2 will more or less be Zope3 + App, DateTime, OFS,
Products and some other stuff. Then something more of a merge might
make sense.

This is a really really good point ;-)
I think unification is probably a good idea, but not yet...

Even so, I'd much prefer to see Z3 stay "light" of Zope 2 and just have
Zope 2 become smaller and smaller as it leverages more and more of Zope 3.

Put differently, I have no problem with the repositories merging, but
I'd like to see the bits of Zope 3 seperately available, without Z2. I
know ZPT and testbrowser already work like that, and the more that works
like that the better...